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These are certainly nice looking pieces, but at what I recall $600, for less than 4 pounds of weight loss it must be one of the most costly weight reductions you could do. With respect to the loss at the "moment of inertia" being detectable with how quickly the engine revs, your behind must be very sensitive to feeling the loss of a pound and a half (weight of the crank pulley alone) being removed from a rotating assembly (on the axis of rotation) that weighs what, 60 plus (?) pounds including the crank etc.
The pulleys are quality looking items, but I'm not convinced they offer a measurable performance gain.
These are certainly nice looking pieces, but at what I recall $600, for less than 4 pounds of weight loss it must be one of the most costly weight reductions you could do. With respect to the loss at the "moment of inertia" being detectable with how quickly the engine revs, your behind must be very sensitive to feeling the loss of a pound and a half (weight of the crank pulley alone) being removed from a rotating assembly (on the axis of rotation) that weighs what, 60 plus (?) pounds including the crank etc.
The pulleys are quality looking items, but I'm not convinced they offer a measurable performance gain.
It's a small gain quite possibly undetectable from the seat but one which would be beneficial with lots of others to make a real noticeable difference, I would of had a set if I'd known.....
This is how I lost 500+ lbs weight just threw everything at it...!
Some losses were cost effective, others very expensive overall...it certainly made a big difference which I don't regret doing at all...even more so now the car is so light and powerful for a N/A.
I don't remember the cam gear off the top of my head - is that a steel or is that an aluminum gear?
If steel, I would say to swiss cheese the the stock part if you wanted to make it lighter. If aluminum, you might have some room to drill it but it would have less of an effect. 1.5 lbs seems light for a steel gear that size.
Same with the alternator pulley - the new part looks somewhat like a drilled stock part.
Henry thank you for the kind words here. You are a patient man!
Yes indeed 8 years plus of historical data, dyno data, and all the comments from all the guys who have owned these parts, in nearly a decade, deleted. Seven revisions of data pictures comments praise. Never a harsh word.(perhaps maybe cost..... but they're costly to make.) I think in lieu of sponsorship. Oh well, its not always about the money.
The mass loss is quite beneficial, the intrinsic balance, elastomer damping compounds, and fine balance on a dynamic balancer, make these quiet and spin true. Machining is done against the center bore on all the parts. these are well known in the circle. PCA allowed except timing gear. Some guys posted dyno results of AMA 12 WHP on dyno, on a well prepared turbo motor,(Bret Patton) I personally found 9 whp using the prototypes, just by the swap, again turbo. I've been making these for a decade. A few hundred sets are out there. All over the world.. These are all Al, made in house. All these parts fit all the l4 motors. There is no 16v cam timing gear from me. The timing gear pictured is the 8v item 4deg plus-0-minus. The reduction pulley at 1.8:1 and light alternator pulley are a large reclaim, and now finally the balance shaft gears are aluminum. This is gen7(R7-R) pictured lightest produced more precise and refined and elastomer damped.
Jeff
AKA - FT/Factorytuned
Last edited by FT_Factorytuned; 08-27-2016 at 10:25 AM.
Gorgeous pieces no doubt, but IMHO that 600 dollars would be much better spent on an aluminum flywheel if you truly want to lower moment of inertia; that represents a significantly more substantial decrease in rotating mass and will make a much bigger difference in terms of engine response. But if you already have an aluminum flywheel and pressure plate and still have 600 bucks burning a hole in your pocket, at least these are by far the nicest looking pulleys ive ever seen for a 944.
I'm also guessing that on an individual basis the machining costs for all the milling of the teeth (for the cam gears) is going to be high. If you were making a hundred at a time the cost per part would probably be significantly lower.
Last edited by ddombrowski; 08-31-2021 at 11:53 AM.
Yes while the rotational mass is about 4 pounds lighter in the final revision, torque is not sacrificed, as with a flywheel. These masses assist with reclaim. These were originally designed to RECLAIM the balance shaft system 5hp loss. And for the CAM shaft some degree of adjustment to find power there. There should be a net gain in torque, based on available power. The Sachs fly wheel is a massive motive force once spinning, generating torque, likewise for the balance shafts. With the reduction of the alternator drive down so low and 4 pounds drop in mass off the front, net power goes up, cam timing becomes more accurate belt stretch becomes less an issue.. Nothing like what a light weight fly wheel does because its such a formidable mass.
There are many reasons light weight pulley find thier way to some of the finest and most powerful motors made, and steel flywheels or highly calculated mass flywheels are used. Two different things going on related to torque and motive force.
Thank you fellas for the kind words. Look for my posts in classifieds for these parts and feel free to message or email me regarding these parts, fitment, schedules etc.
08-25-2016, 01:40 PM
